Chicago Pneumatic 749K 1/2" Super Duty Air Impact Wrench 625 FT LBS. CP's most powerful, 1/2" Impact Wrench - 625 ft.-lb. Oil bath "Spring Hammer" clutch mechanism for ultimate power, high durability and reduced vibration. Differential regulator with four positive power settings in forward and ultimate power in reverse. Applications: High volume tire shops. Ultimate Torque: 625 ft.-lbs. Square Drive: 1/2". Std. Bolt Size: 5/8".